1. Plants with ± herbaceous habit and reduced embryo. . . . .
   . . . . . . . . . . . . . . . . . . . . . . Monotropoideae, 2
 2. Plants with chlorophyll. . . . . . . . . . . . . .  . . . .Pyroleae
 2. Plants lacking chlorophyll, i.e., strongly mycotrophic. .  . . . .3
  3. Stamen appendages present; multicellular hairs on leaves 
     present; embryo undeveloped with 30-40 cells.  . . . .Pterosporeae
  3. Stamen appendages absent; multicellular hairs on leaves 
     usually absent; embryo extremely undeveloped, with less
     than 30 cells. . . . . . . . . . . . . . . . . . . . .Monotropeae